How to count duplicate entries in OpenOffice/LibreOffice BASIC? - libreoffice-basic

Question

I have a gnarly amount of data across many sheets in LibreOffice -- an ADDRESS column and a DATA column -- and I'd like to count the number of times each address occurs, put into a NUM_ADDR column. E.g.:
ADDR | DATA | NUM_ADDR
00000000bbfe22d0 | 876d4eb163886d4e | 1
00000000b9dfffd0 | 4661bada6d4661ba | 1
00000000b9dfc3d0 | 5d4b40b4705d4b40 | 1
00000000b9def7d0 | 8f8570a5808f8570 | 1
00000000b9de17d0 | 63876d4eb163886d | 1
00000000b9dddfd0 | 6d4eb163886d4eb1 | 3
00000000b9dddfd0 | 705d4b40b4705d4b |
00000000b9dddfd0 | b4705d4b40b4705d |
00000000b7df83d0 | 40b4705d4b40b470 | 1
00000000b7d607d0 | 705d4b40b4705d4b | 1
...
When doing things manually I used the COUNTIF function on each address, but I've found that a macro would save time in the long run. Here's a snippet of what I have so far, given that a previous function has already determined the length (number of rows) of the data, stored in RowCounter:
Dim CountedAddr(RowCounter, RowCounter) as String
Dim CountedAddrPtr as Integer
Dim CurrentCell as Object
Dim i as Integer
CountedAddrPtr = 0
' Populate CountedAddr array
For i = 1 to RowCounter-1
CurrentCell = CurrentSheet.getCellByPosition(0, i)
If Not CurrentCell.String In CountedAddr(?) Then
CurrentSheet.getCellByPosition(2, i).Value = 1 ' for debugging
CountedAddr(CountedAddrPtr, 0) = CurrentCell.String
CountedAddrPtr = CountedAddrPtr + 1
Else
CurrentSheet.getCellByPosition(2, i).Value = 0 ' for debugging
EndIf
Next
' For each unique address, count number of occurances
For i = 0 to UBound(CountedAddr())
For j = 1 to RowCounter-1
If CurrentSheet.getCellByPosition(0, j).String = CountedAddr(i, 0) Then
CountedAddr(i, 1) = CountedAddr(i, 1)+1
EndIf
Next
Next
' Another function to populate NUM_ADDR from CountedAddr array...
So my first question is: how can we determine if an element (the address in the current cell) is in the CountedAddr array (see the (?) above)? Second, is there a much more efficient way to achieve the second block of code? Unfortunately sorting is out of the question, since the chronology of the addresses and data form something of a time base. Third, is the whole shebang a foolish way to attack this problem?
Many thanks from a hardware dood on a software task!

Answer 1

Dictionary-type objects such as a VB6 Collection are efficient for looking up items, because it finds the key directly rather than looping through a long array. Our countedAddrs collection below will store a count for each address.
Sub CountAddrs
Dim countedAddrs As New Collection
Dim oCurrentSheet As Object
Dim oCurrentCell As Object
Dim currentAddr As String
Dim i As Integer
Dim newCount As Integer
Dim rowCounter As Integer
Const ADDR_COL = 0
Const COUNT_COL = 2
oCurrentSheet = ThisComponent.CurrentController.ActiveSheet
rowCounter = 11
' Populate countedAddrs array.
For i = 1 to rowCounter - 1
oCurrentCell = oCurrentSheet.getCellByPosition(ADDR_COL, i)
currentAddr = oCurrentCell.String
If Contains(countedAddrs, currentAddr) Then
' Increment the count.
newCount = countedAddrs.Item(currentAddr) + 1
countedAddrs.Remove(currentAddr)
countedAddrs.Add(newCount, currentAddr)
oCurrentSheet.getCellByPosition(COUNT_COL, i).Value = newCount ' for debugging
Else
countedAddrs.Add(1, currentAddr)
oCurrentSheet.getCellByPosition(COUNT_COL, i).Value = 1 ' for debugging
EndIf
Next
End Sub
This code requires the following helper function. In most languages, dictionary objects have this functionality built-in, but Basic is rather simplistic.
' Returns True if the collection contains the key, otherwise False.
Function Contains(coll As Collection, key As Variant)
On Error Goto ErrorHandler
coll.Item(key)
Contains = True
Exit Function
ErrorHandler:
Contains = False
End Function